Clock, chroncgraph, and the like



Aug. 19, 1924.

A. STEUART CLOCK. CHRONOGRAPH, AND THE LIKE Filed June 22 1923 2Sheets-Sheet l CLOCK, CHRONOGRAPH, AND THE LIKE Filed June 22. 1923 2Sheets-Sheet 2 ATTX Patented Aug. 19, 1.924.,

UNITED STATES PATENT OFFICE.

ALEXANDER STEWART,

CLOCK, OHRO'NUGlI-API-T, AND THE Application filed June 22,

To all whom it may cancer 22..

it known that l, AJJERTANDER Sr n i a subject of the King of GreatBritain and Ireland, 1 iding at 16 Clarence Street, Edinburgh, county otMid Lothi Scotland, have nrented new and 118911.

irrprovements in and. Relating to Clocks, Chronographs, and the like, ofwhich the following is a specification.

This invention relates to clocks, chronographs and the like, which aredriven by electricity, and has for its object to con struct suchinstruments, or appliances, so as to eliminate the disturbance of thepen dulum or balance wheel, due to the friction of unlocking theimpulse, drivinga count wheel, or working an electric contact. Theunlocking, counting and contact breaking, are in this case all done byan electric motor and not by the pendulum. while the usual intermittentclock motion is replaced by continuous motion.

The invention comprises essentially an electric motor which is kept incontrolled continuous motion, an impulse or maintaining piece, a cam,eccentric, or the like, an electric contact, and a timekeeper such as apendulum, or balance wheel and spring. The device may be provided withclock hands and a dial, a commutator or other contact device, and achronograph drum. with necessary gearing.

The impulse piece, such as a spring or gravity arm, is first set andthen released by the motion of an electric motor acting through a trainof wheels, and a cam, eccentric, or the like.

The pendulum, or balance wheel, receives an impulse from the impulsepiece, which then closes the electric circuit, and electrical energy isthus supplied to the motor.

The motor, in resetting the impulse piece, opens the electric circuit.

The speed of the motor depends on the length of the intervals of timeduring which the electric circuit is closed.

The continuous motion of the motor, during the time when the circuit isnot closed, is maintained by a reduced current which may be shunted pastthe contact, or by kinetic energy stored in the moving parts, or byboth.

The motor is arranged so that it the con tacts were always closed, thespeed would be in excess of the normal speed required OF EDINBURGH,SGQTLAND.

LIKE.

Eerial N0. 347,044.

operate the gravity arm in time with the pendulum. The function of themechanism is to close the contacts only for such intervals as arerequired to maintain normal sp d. A decrease of motor speed wouldincrease the ontact interval and thus accelerate the motor, and,conversely, an increase speed would decrease the contact interval, andslow the motor. In operation the mechanism soon finds the requiredconstant interval to maintain normal speed.

In order that my said invention and the manner of performing the samemay be properly understood, I hereunto append two sheets of explanatorydrawings to be hereinatter referred to in describing my invention.

Figure 1 is a front elevation of one example of the apparatus, andFigures 2 and 3 are similar views of modified forms of the apparatus. Inthese drawings the same reference numerals are used to mark the same orlike parts wherever they are re peated.

is shown in Figure 1 of the drawings, the pendulum 1 is suspended by aspring troin a support 3. The gravity arm 4.- is pivoted at 5 in linewith the bending line ot the spring 2, or it may be suspended by anotherspring. The gravity arm 4 is provided with an inwardly projecting memberand a contact 7. A lifting arm or lever 8 having a plurality of members,is posi tioned below the gravity arm 1, and pivoted at 9, so that one ofits members 10 contacts at predet rmined times with the free end ot thegravity arm, while the opposite member 11 carries an anti-friction wheel12 adapted to bear against a cam or eccentric 13 operated from the motor14, through a train of wheels indicated by the dotted circles 15 and 16.The remaining member 17 of the lever 8 is shown as positioned at rightangles to the other members, and is provided with a counter-weight 18,to keep the wheel 12 in contact with the cam or eccentric 13, and themovement of the lever 8 in one direction is limited by a stop 19. Thecircuit from the motor 14 is indicated by the dotted lines 20 andintroduced into said circuit is a battery or it might be a dynamo orother source of electrical energy and a resistance 26.

Figure 2 shows a modified and more compact form of the apparatus. Inthis case the lifting arm or lever 8, is suspended from the same pointas the gravity arm lit but on the opposite side of the pendulum l andthe counterweight 18 is incorporate in the anti-friction wheel 1?,contactino' with the cam 13 the latter eing interposeo between thegravity arm t and. the li'i tinfi arm, 8. As the gravity arm t with itsme her 6" and the lifting arm 8 with its mem her 10, in this case, workand meet behind (or before) the pendulum l, the latter is driven by aprojecting pin 22, fixed on the member 6 of the gravity arm 4-".

Figure 3 shows a term of the apparatus in which the impulse is appliedat the tree or lower end of the pendulum by the momher 6 of the gravityarm 4:, 'iivoted at 5 acting on a roll r 23, serving as a pallet. Themovement oi the gravity arm 4-, a. :l lifting arm 8", the latter pivotedat 9 in this case, up and down, instead of rigid. and left ashereinhetore descrihed, so that the former does not contact with thependulum, 1* until the latter has approximately completed its returnsupplementary a r. otherwise the action is the same as that de scribedwith reference to Figures 1 and Referringespecially to Fig. 1 in ope:tion the action of the apparatus is as lows :-The pendulum l is operatedhr he motor 14, which through the cam l3 and lever 8 raises the gravityarm 4-, so that when descending or returning. its memher 6 pressesagainst and swings the pendulum to the right. The arm 4 will he arrestedwhen its Contact 7 strikes the fixed, contact 24., thus completing thecircuit, when current will pass from the hattery 95 o the motor 14. Thependulum 1 will cont nue to swine; to the right" and the suppleuieut:arc may exceed the impulse are it desired During the supplementaryswing; of the pendulum 1, to the right the cam fl tinues rotating andreleases the wheel when the lever 8 will move to the lett breaking thecontact aetweeu the contacts 7 and 24;. and raising; the gravity arui tuntil the lever 8 is arrested by the fixed stop 19.

on the return swing, to the left. the pendulum 1 will lift the gravityarm 4. from the lever 8i and will complete its supplementary arc in thatdirection while the cam 13in rotating will move the arm ot the lever 8to the right, to allow the gravity arm 4 to descend until the contacts 7and 24 again close or meet.

lVith the usual seconds pendulum the cam makes one revolution in twoseconds.

The gravity arm 1- and also the lit-t arm 8 may be duplicated to give animpulse CPU 4 second or the cam or eccentric l3 driven more slowly, sothat the im- ,7 re at long r intervals than t o secdurinp such iii rvalsthe lifting; iii-Tu holc the ejrzivit arm 4 clear of the ulum 1.. whichwill swing freely in stence 36 preveii's sparking; the contact andcurrent o Keep the motor l t. in motio the contacts are while tor 14,and esistance regulated that the sahoi'e the norma t: kept closed andspeed with the contacts rcpt open.

lt will he ohvious that whilst the i'noa'emeut of the peudulun'i l isohta ned trom the motor 14:. yet the 'Former controls or governs thespeed of the latter.

The motor, controlled as hereiuhel ore de scrihed may he utilized forexample in conuectiou with the driving oi clocl: hands rrcordiug drumsand telescopes" The device may drive such appliances ineclmnicullin ormay operate an electric contact or rouuuu tutor. to provide impulses ofcurrent at regular intervals. and so operate cont ol he applianceselectrically at a distance in the usual manner.

ll hat I claim is:

i. 1. electric clocic. comprising a cloch mechaiusim an electric motorha ing a ow i'inuously rotat ihle memher operativelv con-- uc d to saidmechanism, an electric cirtor supplyino current to said motor andincluding): a movahle Contact and a tired contact adapted to control thespeed of the n liifll', an a ni carrying; laid movahle cor.- turi and ped hy the clock mechanism to open said. rou -r and an osrillatoiy them--her adapted to receive its impulse from said ifllll and threuo h it tocontrol the ole-sine o't aid contacts.

Au electric clock, comprising a clot-l? inechai' isnr an elect ic motorhavinq' a contimioush ro atahle member operatively con n cted to saidinechauisnn an electric cirru t For supplyiug currei'i; to said motorand including); a inovahlc contact and a fixed con act adapted tocontrol the speed x i the motoih a gravity arm carrying said movahlecontact and operated by the clo mechan sm to open said contacts and apenduluni adapted to receive its inioulse from said arm and through itto control the closing; oil said contacts.

in testimony whereof I have signed, luv name to this specification. i

